The exterior of a building housing the Jyllands-Posten Copenhagen office is seen. Four Swedes accused of plotting a revenge attack on the Jyllands-Posten newspaper that printed caricatures of the Prophet Muhammad have gone on trial

Four men went on trial in Denmark on Friday accused of planning a “Mumbai-style” terror attack on the offices of a Danish newspaper whose publication of cartoons of the Prophet Mohammad in 2005 outraged many Muslims.

The men, three Swedish citizens and one Tunisian, pleaded not guilty to involvement in the worst terrorist plot in Denmark to date, denying allegations they had planned to kill a large number of people at the offices of the paper, Jyllands-Posten.

“It is our perception that an unknown number of people were to be killed by shooting,” Chief Prosecutor Gyrithe Ulrich told TV2 News outside the courthouse in Glostrup, near Copenhagen.

Jyllands-Posten was the first to print a dozen cartoons lampooning Islam in 2005, triggering protests against Danish interests abroad and riots in countries from the Middle East and Africa to Asia the following year in which at least 50 people died.

Denmark’s state security police (PET) has said the planned attack was modelled on a 2008 shooting spree in Mumbai, when 10 Pakistani gunmen killed 166 people in a three-day assault at city landmarks, including two hotels and a Jewish centre.

The men belonged to a militant Islamist group and had links to international terrorist networks, the PET has said.

The four were arrested in a joint Danish-Swedish police operation in the suburbs of Copenhagen and Stockholm on Dec. 29, 2010. Police, who had been tracking the men for some time, have said that the attack was imminent “within days”.

All four pleaded not guilty to the main charge of terrorism, but Dhari pleaded guilty to the charge of illegally possessing weapons, which the others denied.